Who Controls the World's Underwater Internet?

The Internet Has a Hidden Foundation

When you send a message to someone on another continent, watch a video hosted overseas, or transfer money internationally, your data may travel through a cable lying on the ocean floor.

These submarine cables form the physical backbone of the global internet. Thin strands of glass carry information as pulses of light across thousands of kilometres, connecting countries and continents at extraordinary speeds.

Satellites also carry internet traffic, but submarine fiber-optic cables handle the overwhelming majority of intercontinental data transmission. They support everything from video calls and cloud computing to international banking and government communications.

Yet most people rarely think about them.

The internet feels like something that exists in the air, accessible from anywhere with a signal. In reality, much of our digital world depends on infrastructure that can be damaged, disrupted, or targeted.

And that raises an important question: who controls it?

No Single Country Owns the Internet Under the Sea

There is no single government that owns or controls the world's underwater internet cables.

Many are financed, built, and operated by groups of telecommunications companies, technology firms, and infrastructure investors. Their ownership arrangements vary from system to system.

For decades, telecommunications companies played the leading role in building international cable networks. More recently, technology giants such as Google, Meta, Microsoft, and Amazon have invested in cables to support their global data centers and cloud services.

These companies need reliable, high-capacity connections to move enormous quantities of data between continents.

Their investments can improve capacity and create alternative routes. But they also mean that a growing share of critical internet infrastructure is connected to the commercial interests of a relatively small number of powerful companies.

Owning a cable does not mean controlling every message that travels through it. However, ownership can influence where capacity is built, which routes receive investment, and how much infrastructure is available to different regions.

Why the Routes Matter

Underwater cables do not follow random paths.

They connect major internet hubs, avoid difficult terrain where possible, and pass through coastal landing stations where submarine systems connect to land-based networks.

Certain places have become especially important because several cables converge there.

The Red Sea, for example, provides a major connection between Europe and Asia. Cables crossing this region pass through waters near the Bab el-Mandeb Strait, a narrow passage already important to international shipping.

Disruptions in the area can threaten multiple cable systems. In February 2024, damage to several submarine cables in the Red Sea disrupted internet connectivity in parts of Africa and Asia, highlighting the vulnerability of concentrated routes.

Countries near these connections may gain strategic importance simply because so much international data passes nearby.

How Can an Underwater Cable Become a Security Risk?

Submarine cables are vulnerable to accidental damage from ship anchors, fishing activities, earthquakes, and underwater landslides. Repairs can be difficult because specialized vessels must locate the fault and reach the damaged section.

But governments also worry about deliberate interference.

A damaged cable can slow connections, increase costs, and interrupt services. If several important cables fail in a region with limited alternatives, the consequences can be much worse.

Governments have also raised concerns about surveillance, sabotage, and the security of cable infrastructure built or maintained by companies linked to rival states.

However, a cable break is not automatically evidence of an attack. Determining whether damage was accidental or deliberate requires evidence.

Countries are responding by improving monitoring, strengthening repair arrangements, and encouraging more diverse cable routes.

The Next Battle May Be About Connectivity

As artificial intelligence, cloud computing, and international digital services expand, demand for reliable global data connections will continue to grow.

That makes submarine cables more than commercial infrastructure. They are part of the systems that support modern economies, financial markets, and national security.

A country can build powerful technology companies and modern data centers, but those advantages mean less if its international connections are unreliable.

The challenge is that building alternative routes takes money, time, and cooperation between countries and private companies.

No nation can easily replace the entire network on its own.

The Loose End

The internet appears borderless, but its physical foundations are concentrated in cables, landing stations, and routes that cross specific territories and waters.

The companies that build these systems do not control the whole internet, and the countries near them do not automatically control the data passing through them. Yet both can influence the infrastructure on which everyone else depends.

If the world's digital economy relies on cables hidden beneath the ocean, how secure can the internet really be when so much of its physical foundation remains out of sight?